What follows is a brief description of the electro-magnetic telegraph used to provide telegraph service at the Willow Bunch Telegraph Office between 1904 and 1931. Please see the Telegraph Office History page for background information on the Willow Bunch Telegraph Office and a detailed history of the property.
The electro-magnetic telegraph is a system for human-to-human transmission of coded messages. The systems in use at the early 1900s in North America (United States and Canada) were based on that originally developed and patented in the United States in 1837 by Samuel Morse. These systems used American Morse code for message encoding.
Morse code is a method of transmitting text information as a series of dot and dashes. Each character (letter, numeral, or punctuation) is represented by a unique sequence of dots and dashes as shown below.
Abbreviations (usually made by dropping vowels) were used to shorten the length of messages and lessen the operator's work. Numerical signals like the following were also used to shorten for frequently used wire signals:
|1.||Wait a minute.|
|3.||Give me the correct time.|
|4.||Where shall I repeat from?|
|5.||Have any business for me?|
|6.||I have business; are you ready?|
|8.||Close your key; you are breaking.|
|9.||Attention or clear the wire.|
|14.||What is the weather?|
|17.||Daily weather report.|
|18.||What the trouble?|
|22.||Busy on other wire.|
|30.||Finished, the end-used mainly by press telegraphers.|
|73.||My compliments, or Best Regards.|
|134.||Who is at the key?|
The following is a simplified circuit diagram for the Willow Bunch to Moose Jaw telegraph line. This diagram shows the basic equipment that was in use and how they were connected.
Each site would have also had a lightning arrester on the line(s) coming in from the telegraph poles to protect the equipment and building from lightning strikes on the line. The Moose Jaw site would have also had one or more switchboards as well more sets of the basic equipment shown here for other incoming lines (e.g. the one from Regina).
Intermediate sites, like Wood Mountain, would also have had a simple switchboard for the main line wire coming in and out of the site. The main line wire came into the switchboard from each direction, and was then connected to the instruments on the operator's table. This put the site's equipment (relay magnets and the key) in series with the main line circuit. The switchboard had a ground wire available on it and means of opening the line circuit on each side of the instruments in the office and attaching the ground wire in place of the line wire. This was provided so that if the line wire were to be broken down or burned down by lightning in one direction or the other, the operator could temporarily connect the ground wire and thus restore communications with the office(s) in the opposite direction from the break in the line. For example, if the line was down between Wood Mountain and Moose Jaw, the operator in Wood Mountain could easily reconfigure his switch board so that he could still communicate with Willow Bunch.
As mention in the Telegraph Office History, the line between Willow Bunch and Moose Jaw was expanded with the addition of loops to Gravelbourg (1910) and Assiniboia (1912). Those two sites would have looked just like that for Wood Mountain in the above simplified circuit and would have included a simple switchboard as mentioned above.
The telegraph system used a single wire, hung in the air on wooden poles, between each location. This wire was only half of what was need to complete the circuit. The other half was provided by the earth, very much like our AC power systems do today. Ground rods were used to connect the telegraph equipment to the earth. The ground rods shown in the photo on the right are the actual ground rods that were in use at the Willow Bunch Telegraph Office. They were recovered during the excavation for the new basement. All of the rods were installed within a few inches of each other, which indicates they were installed at different times. That is, as a rod became corroded and ineffective and new one was installed (pounded into the ground) to take its place. The longest at the right, was the one that was in use at the time the Willow Bunch Telegraph Office closed on September 1, 1931.
The ground rods mentioned above are the only remaining artifacts from the telegraph system used at the Willow Bunch Telegraph Office. The key, relay, and sounder described and shown below are very similar to what would have been in used at the Willow Bunch Telegraph Office but they are not the originals. These artifacts were acquired elsewhere for a small museum that will eventually be setup at the restored Willow Bunch Telegraph Office.
When the Willow Bunch Telegraph Office opened there was no electrical service like we have today, so the telegraph system had to be powered by batteries. The batteries in use were called Gravity batteries (as known as crow-foot batteries). They were quite different then modern batteries, although their operation was similar in principal. Gravity batteries consisted of a glass jar, a zinc "negative" pole at the top of the jar (the crow-foot looking thing with the wire attached), a copper pole at the bottom of the jar (the fanned out bar with the wire attached), blue vitriol placed around the copper at the bottom of the jar, and water to fill the jar. This arrangement of components and the chemical action between them is what produced the electrical current needed to power the telegraph system.
The telegraph system used two separate batteries. One main battery (attached to the telegraph key) to power the signal sent over the wire between the locations and a local battery to power the sounder.
The telegraph key is what the operator would use to send messages encoded in Morse Code. Depressing the key (large black knob) would close (make) the circuit. Then releasing it would open (break) the circuit. The making and braking of the circuit is what caused the sounders along the line to emit clicking sounds and hence communicate the dots and dashes of Morse Code. The key also had a switch (smaller black knob) which was used to close the circuit when the key is not in use. The switch had to be left closed to make the circuit so others on the line could use the system.
The telegraph relay is used to convert the very low line current to a higher local current needed to drive the sounder.
The Telegraph Sounder produced the clicking sound (dots and dashes) based on the signal received over the line.
That concludes the very brief description of the electro-magnetic telegraph used to provide telegraph service at the Willow Bunch Telegraph Office. If you are interested in learning more about the system please check out some of the Further Reading material below.
At some point in time an attempt will be made setup a desk and telegraph equipment like would have been used by Mark Noel at the Willow Bunch Telegraph Office. When that happens I will update this page accordingly.